“What makes a difference?” That was the question put to the heads of the 21 most improved state schools in the country by Michael Bichard, permanent secretary at the Department for Education and Employment, on Tuesday.

The heads and deputies had been invited to a seminar organised by the department’s school effectiveness unit to “celebrate” their success, to say how they had achieved it - and to pass ideas on to ministers and officials. The event was organised for the day the secondary school tables, which now include rankings of improvement during the past four years.

The first step towards success, according to John Clinton, head of St Alban’s, a Roman Catholic voluntary-aided comprehensive in Ipswich, was to draw up a clear new mission statement stressing the school’s dual commitment to learning and the Christian ethos. He followed this by revising the job descriptions of his senior management team and heads of department, setting out not only what they were to do but how they were to do it.

Then followed analysis of the figures and target-setting for individual departments and pupils. Pupils were “tracked”, initially in Year 11 and now all the way down to Year 7, with individual targets set for each half term and teacher mentors to keep them on track. Departments would indicate “borderline pupils” and say what pupils and staff needed to do to improve their performance.

This kind of close analysis of the figures and monitoring of individual pupils was frequently mentioned during the day. As Steven Andrews, himself a successful head in Hertfordshire until he joined the school effectiveness unit in September, remarked to the assembled heads: “You have no fear of measuring. ”

Lyndon Jones, the former FE college principal brought in to head Harris City Technology College in Croydon, warned against concentrating only on success in grades A to C at GCSE. “Don’t ignore A to G as a stepping stone,” he told his colleagues. Ensuring no pupil left without at least one A to G grade was “politically very important”.

When John Swinburn took over as head of Cheslyn Hay High School, a local authority comprehensive in Staffordshire, in 1985, he found the figures showed “a terrible problem with boys” - about a 20 per cent gap between the number getting five A to Cs and the number of girls achieving that level.

A combination of mentoring (using tough and successful male teachers for the boys), the use of luridly coloured personal organisers and changes in classroom management had boosted the achievement of all pupils and narrowed the gap between girls and boys, Mr Swinburn said.

In 1997, 54 per cent of boys got five A to Cs,compared with 69 per cent of the girls.

“You’ve got to get rid of the rubbish teachers,” said Andy Halpin of Harris CTC. “You’ve got to recognise the damage that can be done and the unnecessary waste.”

But as education minister Estelle Morris pointed out during the seminar, it was very hard to get across the message criticising poor teachers. It always seemed to upset the best teachers most, perhaps because they were the most self-critical, she suggested.

She also entered a word of warning about the need for a sophisticated approach to school improvement. Some schools might feel they were doing everything the most improved schools were doing and yet it was not working for them, she said. Even the heads at the seminar might not have been so successful in other schools.

Performance tables, 52-page pull-out